Steam-engine.



UNITED STATES PATENT Patented August 4, 1903;

OFFICE.

STEAM-ENGINE.

SPECIFICATION forming part of Letters Patent No. 735,220, dated August 4, 1903.

Application filed October 11, 1902. Serial No. 126,819. 7 (No model.)

To all whom it may concern.-

Be itknown that I, HENRY L. DIGKSQN, a citizen of the United States, residing at Smithville,in the county of Bastrop and State of Texas, have invented certain new and useful Improvements in Steam-Engines; and I do hereby declare the following to be a full, clear, and exact description ofthe invention, such as will enable others skilled in the art to which it appertains to make and use the same.

Ordinarily only large slow-speed engines are advantageously of the Corliss type.

An object of this invention is to provide for engines of this type a simple construction that shallbe equally adapted for locomotives and for high-speed engines generally, whatever their size.

In the accompanying drawings, Figure 1 shows in side elevation a common engine-cylinder provided with my novel devices. Figs. 2 and 3 show, respectively, a certain slide and a slide-operating lever, both of which are seen also in'Fig. 1. Figs. 4, 5, 6, and 7 are sections on the lines 4 4, 5 5, 6 6, and 7 7, respectively, of Fig. 1. Fig. 8 is anend view of a certain reciprocating bar having a trip connected thereto.

In the figures, A represents an engine-cylinder of rectangular outline, having near its upper corners, respectively, two inlet-valves and below two corresponding exhaust-valves, all these valves in construction and location presenting no novelty whatever. The exhaust-valves are operated by an engine eccentric-rod B, acting through eccentrically-pivoted disks 0 G and connecting-pitmen 6 all without novelty. From the lateral margins of the cylinder project flanges A, which serve as a way for a vertically-moving support D, having a horizontal ledge or offset D and provided with vertically-elongated holes D near its ends to allow the passage of stud-bolts D which screw into the cylinder A. Upon the offset D rests a slide-bar E, held in place by an angle-bar E, bolted to the upper edge of the support D and caused to reciprocate 'by an ordinary engine eccentric-rod B. Upon the ends of the bar E, respectively, are ad.- justably. secured oppositely-turned wedgepointed trips E by which, as will be seen, the admission-valves are opened. To the valvestems F, Fig. 6, are fixed oblique heads G, to which are adjustably secured catch-blocks G, to be alternately engaged by the trips E respectively, as the slide-bar E reciprocates. When the slide-bar so movesthat the vertical side of a trip meetsit-s catch, it pushes the latter aside, and thus rotates the valve-stem, opening the corresponding valve. When the trip in passing on releases the catch, the valve is instantly closed by means of approximately parallel springs H H, held at their middles by a boss H and a keeper H and normally pressing opposite sides of an elongated camlike projection G upon the head Gr. As the head is forced to rotate by the trip the cam presses the springs apart, as seen at the right in Fig. 1, and to lessen friction each working face of the cam is provided with a roller G When eithertrip so moves that the oblique side strikes its catch, the valve is moved in the closing direction beyond its normal position. This movement is, however, very slight, for the reason that the catch lies far to one side of the perpendicular from the axis of the valve-stem to the path of the trip, where it lifts rapidly in moving still farther to one side. This position of the catch is of the greatest importance for the further reason that the catch moves toward and then to the opposite side of that perpendicular in opening the valve, whereby the valve is opened suddenly and held open for a relatively long time. that the catch is adjustable at will by sliding longitudinally, which in effect changes its angular adjustment about the valve-stem and varies its distance from the perpendic-- ular. In this case, as before, the springs restore the valves to normal position as soon as the trips permit. For a given ad justment of the catches the valves are held open during a fraction of the stroke, which depends upon the depth of the engagement of It is also of importance to observe the trips and catches. This depth may ob viously be varied by raising the trips or by lowering the catches; yet the two methods of adjustment are far from being equivalent. If the trips be raised, they still begin to engage the trips at almost precisely the same point in the stroke; but they release later than before. If the like depth of engagement be secured by lowering the catches, the latter will necessarily pass far toward the ends of the paths of the trips, and hence engagement will begin much earlier in the stroke. In the one adjustment the interval during which the valves remain open varies much more rapidly than the time of opening, while in the other adjustment the converse is true. The oblique adjustment of the catches gives, then, in itself several novel results, and taken in connection with the trip adjustment it makes still other results possible. For example, if we lower the catches, moving them obliquely outward, of course, and then correspondingly lower the trips we may materially vary the time of opening without in the slightest degree changing the interval during which each remains open. The extent of engagement may also be varied from time to time during the operation of the engine by means of a lever I, actuated by the engine-governor or otherwise, as desired. Both stud-bolts D pass through this lever, the one fitting its aperture closely and serving as a fulcrum and the second lying in a vertical slot D in the lever, and thus offering no resistance to swinging the latter slightly upon its fulcrum. The lever is provided with a horizontal slot 1, in which fits a block D loosely mounted upon a stud D fixed to the support D approximately in its medial line. Now when the lever is raised by decreased speed of the governor or otherwise the support D is raised in its ways and the degree of the engagement of the trips is increased, which, as has been seen, increases the amount of steam admitted. Excessive speed of the governor or lowering the lever by other agency evidently has a contrary effect and may even cut off all steam if the lowering be sufficient to leave the catches above the path of the trips.

Two admission-valves are shown, because I prefer not to govern two ports by a single valve.

For protecting the working parts upon the cylinder I provide a door J, hinged to the cylinder and so constructed as to cover these parts when closed and to fit closely at all points except about the eccentric-rods and the projecting end of the lever, where space is allowed for slight lateral movements of these members.

What I claim is 1. The combination with a rotary steamadmission valve, of a spring resisting movement of the valvefrom its port-closing position, a catch connected with the valve-stem to rotate it, a reciprocating bar alongside the catch, a trip secured to the bar in position to engage the catch, a lever swinging upon a fixed fulcrum toward and away from the catch, and a support for said bar pivotally connected with the lever and accompanying it in its movements.

2. The combination with a cylinder provided with a suitable way, of rotary admission-valves, catches borne by the valve-stems, respectively, a longitudinally-reciprocating bar alongside the catches, a support for said bar movable in said way toward and away from the catches, and means for moving said support in its way.

3. The combination with a cylinder, of two rotary admission-valves, catches secured to the valve-stems, respectively, a bar reciproeating alongside said catches, trips borne by said bar in position to engage said catches, respectively, a movable support forming a way for said bar, and means for moving both ends of said support equally in lines perpendicular to a line joining the points of said catches.

4. The combination with an engine-cylinder, of two rotary admission-valves, a slidebar reciprocating in proximity to the valvestems, catches secured to the valve stems, respectively, at one side of their axes and adjustable obliquely toward the path of said bar, trips projecting from the bar in position to engage the catches,respectively, andmeans for adjusting the proximity of the bar to the catches.

5. The combination with an engine-cylinder having two rotary admission-valves, of catches secured to the valve-stems respec tively, springs resisting movement of the valve-stems from valve closing position, a longitudinally-reciprocating bar alongside the valve-stems, trips projecting from the bar. in position to engage the catches, respectively, a support, for said reciprocating bar, movable in a way upon the cylinder toward and away from the valve-stems, and a lever arranged for moving said support in its way.

6. The combination with the engine-cylinder and the two rotary admission-valves, of the non-cylindrical heads on the valve-stems, rollers mounted in said heads, springs working against said rollers and resisting rotation of the valves, catches projecting from said heads, respectively, a reciprocating bar provided with projecting trips to engage the catches, respectively, a movable support for said bar, and a pivoted lever sustaining said support and arranged to swing the samebodily toward and away from the valve-stems.

7. The combination with the cylinder and the rotary admission-valves having on their stems faces oppositely inclined to a line j oining the stems, catches fixed to the stems and adjustable along said surfaces, respectively, springs resisting the opening of the valves,

ICC

a bar reciprocating alongside the catches, and support compelling the latter to move trips secured to said bar in position to engage with the former. 10 the catches, respectively, as the bar recipro- In testimony whereof I affix my signature cates, a support for said bar movable toward in presence of two witnesses.

5 and from'the catches in ways upon the cylin- H. L. DIOKSON.

' der, a lever pivoted to the cylinder to swing Witnesses:

toward and away from the catches, and a WALLACE GREENE,

self-adjusting connection between the lever J. JEROME LIGHTFOOT. 

